The economic and fast torch cutting of different thicknesses of steel with oxygen has had an unchanged importance for more than 60 years, because of the meaning of continuous casting of steel it became an even more important development work in research and in practice. Roger S. Babcock explains in his patent U.S. Pat. No. 2,521,199 according to application dated Jun. 14, 1947 his conclusions and suggestions for economic fast cutting with high pressures of 450 PSI (31.7 bar) to 600 PSI (35.2 bar) and divergent nozzles. Many of these conclusions are still valid, however, the high-oxygen cutting was not accepted in the fields in which approx. 15 bar nozzle supply pressure=working pressure is used today, even though there have been numerous developments and practical tests because of the possible advantages. A proper, permanent, reliable operation with gaseous high pressure oxygen of 15 to over 100 bar working pressure did not seem possible.
Although the outlet pressures and the jet speeds during high-pressure oxygen cutting were known and could be influenced, the operational influences and circumstances were not considered, as Roger S. Babcock showed poorly in FIG. 1 of his a.m. patent. A pressure and flow control of the cutting oxygen by a liquid oxygen pump in front of an evaporator (2) with a receptacle behind also used for pressure measurement and a pressure switch that turns the pump motor on and off was absolutely insufficient. In addition there was only a shutoff valve for turning the cutting oxygen on and off. With the described supply and pipe system and its very general definition of nozzle measurements, good cutting results were achieved under test circumstances, however, not permanently in practical operation. This also applies for all known equipment for high pressure oxygen-torch cutting, apart from torch cutting with liquid oxygen where minimum pressure deviations are of minor influence.